1. Field of the Invention
The invention relates to additives useful for reducing the concentration of acids in hydrocarbons. The invention particularly relates to additives useful for reducing the concentration of carboxylic acids in hydrocarbons.
2. Background of the Art
Hydrocarbons, such as crude oil, may contain acids in several forms. These acids may be mineral acids such as hydrochloric, phosphoric, hydrogen sulfide and various oxidized form of hydrogen sulfide such as sulfuric acid. Organic acids are also common in hydrocarbons.
The most common form of organic acids is carboxylic acids. Such acids are characterized by a labile hydrogen associated with an oxygen which itself is adjacent to a carbonyl group. This structure is commonly shown as in the art as having a general formula R—CO2H. While lower molecular weight carboxylic acids may be easily removed from hydrocarbons by washing with dilute bases, higher molecular weight organic acids are not always so easily removed. Also, some carboxylic acids may be produced during refining. Finally, water washes to remove acids may, in some situations, create new problems of greater scope than the carboxylic acids being removed.
Problems caused by carboxylic acids may include corrosion and fouling. Further, when in acid form, carboxylic acids may be easily distilled and thus be found in refined products. It may be desirable in the art of producing or refining hydrocarbons to reduce or eliminate the amount of carboxylic acids from crude and refined hydrocarbons using an additive.